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Objective: To compare 2 point-of-care lateral flow assays (LFAs) with immunodiffusion (ID) IgG results for anti-coccidioidal antibody detection in dogs with coccidioidomycosis. A further aim was to compare the quantifiable output of 1 of the LFAs to ID antibody titers., Sample: Serum banked from 73 client-owned dogs diagnosed with pulmonary or disseminated coccidioidomycosis., Methods: ID was used to determine antibody presence and titer against a coccidioidal antigen preparation. All sera were subsequently tested on an LFA based on recombinant chitinase 1 (CTS1) and the commercially available sōna LFA. LFA results were analyzed and compared to ID IgG results and clinical diagnosis., Results: All assays showed similar sensitivities in detecting anti-coccidioidal antibodies (83.6% to 89.0%). When compared with ID IgG, the CTS1 LFA had a positive percent agreement of 100%, while the sōna LFA had a positive percent agreement of 91.4%. Since the CTS1 LFA is semiquantitative, we were able to compare test line densities with ID titers and found a strong correlation between the 2 assays (Spearman ρ = 0.82)., Clinical Relevance: This is the first side-by-side evaluation of a commercially available LFA (sōna) and a newer more rapid anti-CTS1 antibody LFA using serum from dogs with coccidioidomycosis. Both LFAs tested have similar sensitivity to ID IgG results. The CTS1 LFA can be read after 10 minutes and is semiquantitative, while the sōna LFA is read after 30 minutes, and the results are subject to interpretation. Accurate and fast detection of anti-coccidioidal antibodies allows clinicians to initiate appropriate treatment without diagnostic delay.

Pulmonary coccidioidomycosis is a relatively common fungal disorder in dogs that have lived in or traveled to endemic regions and fluconazole is a common antifungal treatment. Liver enzymopathy can occur with fluconazole administration, but the frequency of occurrence nor potentially associative factors have been explored in dogs with pulmonary coccidioidomycosis. Therefore, our objectives were to describe the occurrence and magnitude of liver enzyme activity (LEA) elevation in dogs with pulmonary coccidioidomycosis during treatment with per os fluconazole and identify variables associated with liver enzymopathy. This was a retrospective observational study that analyzed serum biochemical data obtained from a separate prospective study that included 32 client-owned dogs with newly diagnosed pulmonary coccidioidomycosis from October 2020 to February 2021. Per os fluconazole administration (median dosage: 16.2 mg/kg/day) was initiated after diagnosis and dogs were evaluated once every 3 months thereafter until remission or for a maximum of 12 months. Recorded biochemical parameters at each visit (including baseline) included alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT). Magnitude of increased LEA was based on the fold increase above the upper limit of the reference interval and defined as mild (<5×), moderate (5-10×) or severe (>10×). Forty-seven percent (15/32) of dogs were documented to have elevations in one or more LEAs after initiation of fluconazole administration during the study period. Thirty-four percent and 25% of dogs had elevated ALP and ALT activities, respectively, at some point during treatment. Elevations in AST and GGT activities were rare. The magnitude of LEA elevation was mild in all cases. Logistic regression models did not identify associations between age, weight, sex, neutered status, prednisone administration, fluconazole dose or duration of treatment with the occurrence of liver enzymopathy. Approximately half of dogs with pulmonary coccidioidomycosis are expected to develop mild increases in activities of ALP and/or ALT with rare involvement of AST or GGT at some point during treatment with fluconazole up to 12 months. [ABSTRACT FROM AUTHOR]